* SUCH DAMAGE.
*/
-#ifndef lint
-static const char rcsid[] _U_ =
- "@(#) $Header: /tcpdump/master/tcpdump/print-mpls.c,v 1.14 2005-07-05 09:38:19 hannes Exp $ (LBL)";
-#endif
+/* \summary: Multi-Protocol Label Switching (MPLS) printer */
#ifdef HAVE_CONFIG_H
-#include "config.h"
+#include <config.h>
#endif
-#include <tcpdump-stdinc.h>
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
+#include "netdissect-stdinc.h"
-#include "addrtoname.h"
-#include "interface.h"
-#include "extract.h" /* must come after interface.h */
+#include "netdissect.h"
+#include "extract.h"
#include "mpls.h"
static const char *mpls_labelname[] = {
* RFC3032: MPLS label stack encoding
*/
void
-mpls_print(const u_char *bp, u_int length)
+mpls_print(netdissect_options *ndo, const u_char *bp, u_int length)
{
const u_char *p;
- u_int32_t label_entry;
- u_int16_t label_stack_depth = 0;
+ uint32_t label_entry;
+ uint16_t label_stack_depth = 0;
enum mpls_packet_type pt = PT_UNKNOWN;
+ ndo->ndo_protocol = "mpls";
p = bp;
- printf("MPLS");
+ nd_print_protocol_caps(ndo);
do {
- TCHECK2(*p, sizeof(label_entry));
- label_entry = EXTRACT_32BITS(p);
- printf("%s(label %u",
- (label_stack_depth && vflag) ? "\n\t" : " ",
+ ND_TCHECK_LEN(p, sizeof(label_entry));
+ if (length < sizeof(label_entry))
+ goto trunc;
+ label_entry = GET_BE_U_4(p);
+ ND_PRINT("%s(label %u",
+ (label_stack_depth && ndo->ndo_vflag) ? "\n\t" : " ",
MPLS_LABEL(label_entry));
label_stack_depth++;
- if (vflag &&
+ if (ndo->ndo_vflag &&
MPLS_LABEL(label_entry) < sizeof(mpls_labelname) / sizeof(mpls_labelname[0]))
- printf(" (%s)", mpls_labelname[MPLS_LABEL(label_entry)]);
- printf(", exp %u", MPLS_EXP(label_entry));
+ ND_PRINT(" (%s)", mpls_labelname[MPLS_LABEL(label_entry)]);
+ ND_PRINT(", exp %u", MPLS_EXP(label_entry));
if (MPLS_STACK(label_entry))
- printf(", [S]");
- printf(", ttl %u)", MPLS_TTL(label_entry));
+ ND_PRINT(", [S]");
+ ND_PRINT(", ttl %u)", MPLS_TTL(label_entry));
p += sizeof(label_entry);
+ length -= sizeof(label_entry);
} while (!MPLS_STACK(label_entry));
/*
default:
/*
* Generally there's no indication of protocol in MPLS label
- * encoding, however draft-hsmit-isis-aal5mux-00.txt describes
- * a technique that looks at the first payload byte if the BOS (bottom of stack)
- * bit is set and tries to determine the network layer protocol
- * 0x45-0x4f is IPv4
- * 0x60-0x6f is IPv6
- * 0x81-0x83 is OSI (CLNP,ES-IS,IS-IS)
- * this technique is sometimes known as NULL encapsulation
- * and decoding is particularly useful for control-plane traffic [BGP]
- * which cisco by default sends MPLS encapsulated
+ * encoding.
+ *
+ * However, draft-hsmit-isis-aal5mux-00.txt describes a
+ * technique for encapsulating IS-IS and IP traffic on the
+ * same ATM virtual circuit; you look at the first payload
+ * byte to determine the network layer protocol, based on
+ * the fact that
+ *
+ * 1) the first byte of an IP header is 0x45-0x4f
+ * for IPv4 and 0x60-0x6f for IPv6;
+ *
+ * 2) the first byte of an OSI CLNP packet is 0x81,
+ * the first byte of an OSI ES-IS packet is 0x82,
+ * and the first byte of an OSI IS-IS packet is
+ * 0x83;
+ *
+ * so the network layer protocol can be inferred from the
+ * first byte of the packet, if the protocol is one of the
+ * ones listed above.
+ *
+ * Cisco sends control-plane traffic MPLS-encapsulated in
+ * this fashion.
*/
- if (MPLS_STACK(label_entry)) { /* only do this if the stack bit is set */
- switch(*p) {
-
- case 0x45:
- case 0x46:
- case 0x47:
- case 0x48:
- case 0x49:
- case 0x4a:
- case 0x4b:
- case 0x4c:
- case 0x4d:
- case 0x4e:
- case 0x4f:
- pt = PT_IPV4;
- break;
-
- case 0x60:
- case 0x61:
- case 0x62:
- case 0x63:
- case 0x64:
- case 0x65:
- case 0x66:
- case 0x67:
- case 0x68:
- case 0x69:
- case 0x6a:
- case 0x6b:
- case 0x6c:
- case 0x6d:
- case 0x6e:
- case 0x6f:
- pt = PT_IPV6;
- break;
-
- case 0x81:
- case 0x82:
- case 0x83:
- pt = PT_OSI;
- break;
-
- default:
- /* ok bail out - we did not figure out what it is*/
- break;
- }
+ ND_TCHECK_1(p);
+ if (length < 1) {
+ /* nothing to print */
+ return;
+ }
+ switch(GET_U_1(p)) {
+
+ case 0x45:
+ case 0x46:
+ case 0x47:
+ case 0x48:
+ case 0x49:
+ case 0x4a:
+ case 0x4b:
+ case 0x4c:
+ case 0x4d:
+ case 0x4e:
+ case 0x4f:
+ pt = PT_IPV4;
+ break;
+
+ case 0x60:
+ case 0x61:
+ case 0x62:
+ case 0x63:
+ case 0x64:
+ case 0x65:
+ case 0x66:
+ case 0x67:
+ case 0x68:
+ case 0x69:
+ case 0x6a:
+ case 0x6b:
+ case 0x6c:
+ case 0x6d:
+ case 0x6e:
+ case 0x6f:
+ pt = PT_IPV6;
+ break;
+
+ case 0x81:
+ case 0x82:
+ case 0x83:
+ pt = PT_OSI;
+ break;
+
+ default:
+ /* ok bail out - we did not figure out what it is*/
+ break;
}
}
/*
* Print the payload.
*/
- if (pt == PT_UNKNOWN) {
- if (!suppress_default_print)
- default_print(p, length - (p - bp));
- return;
- }
- if (vflag)
- printf("\n\t");
- else
- printf(" ");
switch (pt) {
+ case PT_UNKNOWN:
+ if (!ndo->ndo_suppress_default_print)
+ ND_DEFAULTPRINT(p, length);
+ break;
case PT_IPV4:
- ip_print(gndo, p, length - (p - bp));
+ ND_PRINT(ndo->ndo_vflag ? "\n\t" : " ");
+ ip_print(ndo, p, length);
break;
case PT_IPV6:
-#ifdef INET6
- ip6_print(p, length - (p - bp));
-#else
- printf("IPv6, length: %u", length);
-#endif
+ ND_PRINT(ndo->ndo_vflag ? "\n\t" : " ");
+ ip6_print(ndo, p, length);
break;
case PT_OSI:
- isoclns_print(p, length - (p - bp), length - (p - bp));
- break;
-
- default:
+ ND_PRINT(ndo->ndo_vflag ? "\n\t" : " ");
+ isoclns_print(ndo, p, length);
break;
}
return;
trunc:
- printf("[|MPLS]");
+ nd_print_trunc(ndo);
}
-
-
-/*
- * Local Variables:
- * c-style: whitesmith
- * c-basic-offset: 8
- * End:
- */
projects / tcpdump / blobdiff